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<div class="titlepage"><div><div><h4 class="title">
<a name="asio.reference.write_at.overload1"></a><a class="link" href="overload1.html" title="write_at (1 of 8 overloads)">write_at (1 of 8
        overloads)</a>
</h4></div></div></div>
<p>
          Write all of the supplied data at the specified offset before returning.
        </p>
<pre class="programlisting">template&lt;
    typename <a class="link" href="../SyncRandomAccessWriteDevice.html" title="Buffer-oriented synchronous random-access write device requirements">SyncRandomAccessWriteDevice</a>,
    typename <a class="link" href="../ConstBufferSequence.html" title="Constant buffer sequence requirements">ConstBufferSequence</a>&gt;
std::size_t write_at(
    SyncRandomAccessWriteDevice &amp; d,
    uint64_t offset,
    const ConstBufferSequence &amp; buffers);
</pre>
<p>
          This function is used to write a certain number of bytes of data to a random
          access device at a specified offset. The call will block until one of the
          following conditions is true:
        </p>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
              All of the data in the supplied buffers has been written. That is,
              the bytes transferred is equal to the sum of the buffer sizes.
            </li>
<li class="listitem">
              An error occurred.
            </li>
</ul></div>
<p>
          This operation is implemented in terms of zero or more calls to the device's
          write_some_at function.
        </p>
<h6>
<a name="asio.reference.write_at.overload1.h0"></a>
          <span><a name="asio.reference.write_at.overload1.parameters"></a></span><a class="link" href="overload1.html#asio.reference.write_at.overload1.parameters">Parameters</a>
        </h6>
<div class="variablelist">
<p class="title"><b></b></p>
<dl>
<dt><span class="term">d</span></dt>
<dd><p>
                The device to which the data is to be written. The type must support
                the SyncRandomAccessWriteDevice concept.
              </p></dd>
<dt><span class="term">offset</span></dt>
<dd><p>
                The offset at which the data will be written.
              </p></dd>
<dt><span class="term">buffers</span></dt>
<dd><p>
                One or more buffers containing the data to be written. The sum of
                the buffer sizes indicates the maximum number of bytes to write to
                the device.
              </p></dd>
</dl>
</div>
<h6>
<a name="asio.reference.write_at.overload1.h1"></a>
          <span><a name="asio.reference.write_at.overload1.return_value"></a></span><a class="link" href="overload1.html#asio.reference.write_at.overload1.return_value">Return
          Value</a>
        </h6>
<p>
          The number of bytes transferred.
        </p>
<h6>
<a name="asio.reference.write_at.overload1.h2"></a>
          <span><a name="asio.reference.write_at.overload1.exceptions"></a></span><a class="link" href="overload1.html#asio.reference.write_at.overload1.exceptions">Exceptions</a>
        </h6>
<div class="variablelist">
<p class="title"><b></b></p>
<dl>
<dt><span class="term">asio::system_error</span></dt>
<dd><p>
                Thrown on failure.
              </p></dd>
</dl>
</div>
<h6>
<a name="asio.reference.write_at.overload1.h3"></a>
          <span><a name="asio.reference.write_at.overload1.example"></a></span><a class="link" href="overload1.html#asio.reference.write_at.overload1.example">Example</a>
        </h6>
<p>
          To write a single data buffer use the <a class="link" href="../buffer.html" title="buffer"><code class="computeroutput">buffer</code></a>
          function as follows:
        </p>
<pre class="programlisting">asio::write_at(d, 42, asio::buffer(data, size));
</pre>
<p>
          See the <a class="link" href="../buffer.html" title="buffer"><code class="computeroutput">buffer</code></a>
          documentation for information on writing multiple buffers in one go, and
          how to use it with arrays, boost::array or std::vector.
        </p>
<h6>
<a name="asio.reference.write_at.overload1.h4"></a>
          <span><a name="asio.reference.write_at.overload1.remarks"></a></span><a class="link" href="overload1.html#asio.reference.write_at.overload1.remarks">Remarks</a>
        </h6>
<p>
          This overload is equivalent to calling:
        </p>
<pre class="programlisting">asio::write_at(
    d, offset, buffers,
    asio::transfer_all());
</pre>
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<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2018 Christopher M. Kohlhoff<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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